New DNA Analysis Shows Aboriginal Australians Are the World's Oldest Society

[wnylib]

2. Besides the distance, there was

a water barrier, which makes the ancestors of indigenous Australians likely the first humans to cross open sea in a boat or raft.

Lower sea levels due to glaciation exposed continental shelf land so that current islands in southern Asia were linked together and to the mainland except for a gap of about 50 to 70 miles beteen those Asian land areas and Australia. So they were either good at boating or excellent swimmers.